Water vessels are powered by a variety of propulsion means including motors or sails. Engine powered vessels unfortunately present problems to the environment. Engines may leak fuel contaminating the water. In addition, the prop and propeller from engines on motor-powered boats may harm subsurface structures as coral or grass flats. Awareness and sensitivity toward the environment have created a demand for water vessels that avoid such problems. Moreover, motor-powered boats have inherent problems including handling large, heavy vessels on land or mechanical failures in the engine.
Many recreational boaters prefer sailing vessels to motor boats. Sailing vessels offer a different challenge in the operation of the vessels by propelling the boat with aid of wind and skill provided by the boater. In addition, there are water vessels available that provide more physical exertion for exercise. Many such water vessels have propellers that are rotated by a pedal means.